This is a pretty ooky:
But this is extraordinarily ooky (watch to the end for the wallop):
The woman in the video says (and I see no particular reason to doubt her) that this is the nickname her recently deceased grandmother called her when she was a little girl and that her four year did not and could not have known that.
This is why the Church investigates such things when brought to her for discernment. She neither buys nor rejects such stories wholesale.
But, of course, many such claims of private revelation, both false and real, never get investigated because it never occurs to the person making the claim to submit it to the Church for investigation.